Pharynx, Larynx, Thyroid and Sinuses

Question 1

What provides motor and sensory function to the larynx?

Answer 1

Branches of the vagus (cranial nerve X)

Question 2

What innervates all intrinsic muscles of the larynx EXCEPT the cricothyroid?

Answer 2

Recurrent laryngeal nerve

Question 3

Where is the larynx located?

Answer 3

Anteriorly in the neck, between C3-C6

Question 4

What can be found anteriorly and laterally to the larynx?

Answer 4

Anteriorly - infrahyoid muscles

Laterally - lobes of the thyroid gland

Question 5

What is the larynx a component of?

Answer 5

The voice box

Question 6

Which arteries supply the larynx?

Answer 6

Superior and inferior laryngeal arteries.

S. (branch of S. Thyroid artery derived from external carotid)
I. (Branch of I. Thyroid artery derived from thyrocervical trunk)

Question 7

In the larynx venous drainage is carried out by…

Answer 7

Superior and inferior laryngeal veins

S. Drains to internal jugular vein via superior thyroid vein
I. Drains to L. Brachiocephalic vein via inferior thyroid vein

Question 8

Name the 3 parts to the pharynx

Answer 8

Nasopharynx
Oropharynx
Laryngopharynx

Question 9

Which cranial nerve provides sensory function to the nasopharynx?

Answer 9

Branch of cranial nerve V - maxillary nerve (V2)

Question 10

Which cranial nerve provides sensory function to the oropharynx?

Answer 10

Cranial nerve IX - glossopharyngeal

Question 11

Which cranial nerve provides sensory function to the laryngopharynx?

Answer 11

Cranial nerve X - vagus

Question 12

Which artery/arteries supply the pharynx?

Answer 12

Branches of the external carotid artery - ascending pharyngeal, lingual, facial and maxillary arteries

Question 13

Which vein/veins are involved in venous drainage of the pharynx?

Answer 13

Pharyngeal venous plexus which drains into the internal jugular

Question 14

What is the origin and insertion of the superior constrictor muscle of the pharynx?

Answer 14

Origin - medial pterygoid plate and pterygomandibular raphe

Insertion - median raphe of pharynx and pharyngeal tubercle

Question 15

What is the origin and insertion of the middle constrictor of the pharynx?

Answer 15

Origin - Greater and lesser horns of hyoid bone and stylohyoid ligament
Insertion - median raphe of pharynx

Question 16

What is the origin and insertion of the inferior constrictor of the pharynx?

Answer 16

Origin - Thyroid cartilage and cricoid cartilage

Insertion - median raphe of pharynx

Question 17

Name the 3 unpaired cartilages of the larynx

Answer 17

Thyroid, cricoid and epiglottis

Question 18

Name the 3 paired cartilages of the larynx

Answer 18

Arytenoid, corniculate, cuneiform

Question 19

Why might a patient develop hypocalcaemia after thyroid surgery?

Answer 19

If parathyroid glands are damaged, devascularised or removed during surgery. Effects may be transient or permanent

Question 20

Where is the thyroid gland located?

Answer 20

C5-T1

Question 21

What supplies blood to the superior part of the thyroid?

Answer 21

Superior thyroid artery which is a branch off the external branch of the common carotid

Question 22

What supplies blood to the inferior part of the thyroid?

Answer 22

Inferior thyroid artery which arises from the thyrocervical trunk which is a branch of the subclavian

Question 23

What is the function of the sternothyroid and thyrohyoid muscles (extrinsic laryngeal muscles)?

Answer 23

Sternothyroid - depress the larynx

Thyrohyoid - elevates the larynx

Question 24

What nerve supplies the cricothyroid muscle?

Answer 24

External branch of superior laryngeal nerve

Question 25

What is the motor and sensory function of the superior laryngeal nerve?

Answer 25

External branch is motor to cricothyroid muscle

Internal branch is sensory to laryngeal mucosa

Question 26

What is the function of the longitudinal muscles of the pharynx?

Answer 26

To shorten and widen the pharynx. Also elevates larynx to prevent food entering airway

Question 27

Where would you create an emergency airway?

Answer 27

Locate depression between thyroid and cricoid cartilage. Indication should be made in cricothyroid membrane

Question 28

What is the function of the intrinsic muscles of the larynx?

Answer 28

Control shape of rima glottidis and length and tension of vocal cords

Question 29

What is the function of the sinuses?

Answer 29

Produce a mucus that protects the nose from pollutants, micro organisms dust and dirt

Question 30

What is the location of the carotid sinus and what does it detect?

Answer 30

Base of the internal carotid artery just above bifurcation of common carotid artery.
Sensitive to arterial pressure changes which is important in regulating and maintaining blood pressure

Question 31

Where do the ducts for the submandibular salivary glands open into the mouth?

Answer 31

Adjacent to the 2nd molar, under the tongue

Question 32

Describe the location of the 4 sinuses

Answer 32

Frontal - most superior of the sinuses just above the eyebrows and close to the midline of the face
Ethmoid - either side of the nose between the eyes
Maxillary - the largest of the sinuses located in the apples of the cheeks
Sphenoid - Most posterior of the sinuses near the ear

Question 33

Why is infection spread easily between the sinuses?

Answer 33

Due to the close proximity of the sinuses and also its continuation with the nasal cavity